Improvement in preserving surfaces of cast or wrought iron



UNITED STATES PATENT OFFICE."

CHARLES FRANCIS LEOPOLD OUDRY, OF PARIS, FRANCE.

IMPROVEMENT IN PRESERVING SURFACES 0F CAST OR WROUGHT IRON.

Specification forming part of Letters Patent No. 22,132, dated November23, 1858.

To all whom it may concern:

Be it known that I, CHARLES FRANCIS LEO- POLD OUDRY, of Paris, in theEmpire of France, have invented a certain new and useful Method ofPreserving (last or WVrought Iron and other Metals Against theDestructive Elfects-ofAir and ater; and I hereby declare that thefollowing to be a full, clear, and exact description of'the same.

My said invention consists in theemployment of a coating ofvarnish orother intermediary substance, which insulates from the copper the objectto be protected and likewise metallizes or secures the adhesion of thecopper to the surface of the said object. The employment of suchintermediary insulating and metallizing coating has the effect, first,of rendering unnecessary the cleaning of the surface ofthe objects madeof cast or wrought iron, zinc, and other metals, and which consists inwashing said objects in acid or otherwise, so as to remove any oxide orforeign matter which. would interfere with the perfect and equaladhesion of the copper with which they are to be coated; secondly, ofavoiding, consequently, the use of acids, a portion of which is likelyto remain on the'object to be coated, notwithstanding repeated washings,and thereby frustrate the beneficial result sought for in coating thesaid object with copper; thirdly, ofdoingaway with the primary bath ofcyanide of copper, which is always uncertain in elfect and expensive,but which is indispensable in the old methods of coating with copper;fourthly, of protecting in a twofold degree the metallic objects--in thefirst place by the intermediary protecting and completely-insulatingcoating, and in the second place by the layer of copper to which 7 anyrequired thickness may be given fifthly,

of diminishing considerably the labor and expense, as well as the netcost of the manufacture, while the operation is conducted with certaintyof result, whereas the means employed in the old method never succeededcompletely, in spite of all the skill of the operator; sixthly, ofenabling the object which is to be subsequently coated with copperto beplunged, when it is covered with its varnish, into a very aciduloussolution of sulphates of copper without danger ofcorrosion, which showsthe superiority with which objects coated with copper in this mannerwill resist the action of moisture, either on sea or on land, saidmoisture being of a much less corrosive nature than a 'solution ofsulphate of copper.

The varnishes or intermediary insulating substances I use areessentially variable according to the nature of the objects to becoated. They areoomposed generally of bitumen,tar,or pitch, gum -copal,benzole, essence of turpentine, rectifiedsulphuricether,caoutchouc,gutta-percha, litharge, minium, white lead,cinnabar, nut-oil, drying linseed-oil, beeswax, plumbago, bronzepowder,and all other substances possessing the same or similar properties.

To enable others skilled in the arts touse'my invention, I shall nowproceed to describe the manner in which I operate.

I apply first, either cold or hot, with abrush or by immersion, on theobject to protected, whatever it may be, an insulating, impermeable, andmetallizing varnish, which dries rapidly, and I apply one or more layersof this varnish, or of different varnishes, until the covering of theobject by the said varnish or' varnishes is perfect, and leaves no partof the surface unprotected. I then plunge the object so coated with itsvarnish into a bath saturated with sulphate of copper, and by means of agalvanic battery the copper is precipitated in the usual way to anyrequired thickness. I

, ed for protection against the destructive action of bullets and otherprojectiles, thehulls of vesselsofwar,andothernavalconstructions. Eachpiece of the blind or blindage being pierced with holes which serve tounite them to one another, these holes should be coated on the insidewith a layer of galvanic or non-galvanic copper, as may be mostconvenient. The bolts or rivets used for this purpose may be made ofcopper orof any other metal; but ifthese bolts, rivets, &c., for sake ofgiving them greater strength, are made of iron, it will be preferable toemploy iron in that part onlyof the shank which corresponds to thethickness of the blind and to mount the two extremities with copper, theheads of the rivets being made to be raised that the copper may adhereto them.

or to project. It may, perhaps, be possible to use bolts of hardwoodwith internal iron cores, which might becoated with a certainthickness of copper.

Although the deposit of copper be considerable on each piece of blind,and although it cannot be separated from it without great difficulty,nevertheless, as a further precaution, I can pierce here and therethrough the surface of the pieces already varnished and metallizedscrew-tap holes a centimeter or more in depth, and then insert in allthese holes screw-rivets with spike or roughened heads that projectslightly, in order that the deposit of galvanic copper may becomeconsolidated with these rivets, which are to be filed down to a levelafter being taken out of the bath, and in order Other means may also beused before or after the galvanization.

As regards injuries sustained by the blinds of ships of war, whetherfrom cannon-balls or other causes, it will always be possible to makepartial or local repairs, either by taking to pieces the parts injuredor laid bare or by careening the vessel and providing local baths, notforgetting, however, to coat previously with varnish and to metallizethe spots which require repair.

This my invention is applicableto the manufacture of various articlesmade of cast or wrought iron, zinc, and other metals, or alloys ofmetals, such ashulls of ships, statues, fountains, vases, railings,balconies, mantle-pieces, fire-fenders, umbrella stands and racks,picture-frames, and others.

Having thus fully described my improvement, what I claim is- 1. Theemployment ot'a varnish, or of successive varnishes, insulating,metallizing, and intermediary, between the object to be coated withcopper (whether the same be metallic or non-metallic) and theprotecting-copper itself, all or part of said varnishes being composedof certain metallic substances united with fat or essential oils, andwith gummy, resinous, bituminous or asphaltic substances, substantiallyas herein described, and forthe purposes set forth.

2. The coating of all kinds of objects with copper by the employment ofone or several varnishes in succession, previous to the galvaniccoppering obtained directly in a bath of sulphate ofcopper-i. 0.,withoutthe intervention of a bath of cyanide of copper, substantially asdescribed herein.

In testimony whereofI have signed my name to this specification beforetwo subscribing witnesses.

OUDR-Y.

